#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
    int a, b, c = 0;
    while (scanf("%d %d %d", &a, &b, &c) != EOF)
        if (a + b > c && a + c > b && b + c > a) {
            if (a == b && b == c)
                printf("Equilateral triangle!\n");
            else if (a == b || b == c || a == c)
                printf("Isosceles triangle!\n");
            else printf("Ordinary triangle!\n");
        }
        else printf("Not a triangle!\n");


    return 0;
}